scrollViewWillEndDragging中的速度单位是什么:withVelocity:targetContentOffset:？

Question

该文件指出它的points(每秒,我假设)？但是,我得到的值在(.5, 3.5)范围内.滚动视图然后在停止之前行进几百个点.实际的初始速度应该是数量级的不同.

Answer 1

它是点/毫秒.从UIScrollView.h:

// called on finger up if the user dragged. velocity is in points/millisecond. targetContentOffset may be changed to adjust where the scroll view comes to rest
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset NS_AVAILABLE_IOS(5_0);

这是来自iOS 7 SDK,由于它们在速度方面的回报非常低,因此看起来更合理.